Replacing the water heater-gctid804062

[Car2n]

I'm installing a new water heater and wondering about the loop to the engine.

1989 Avanti 2955 with a single 460 Cobra.

I'm installing a 6 gallon heater (this coming weekend) much like the original unit and I'd like to know if the heat loop from the engine to the heater is filled with fresh water from the engine cooling system or is it a separate closed loop with antifreeze?

[canoel]

Your 460 Cobra should have a closed cooling system. The water heater will not have it's own supply. It will be part of the engine cooling system, which should be antifreeze.

If you do not have a closed cooling system, and raw water is drawn from the lake/ocean and circulates through your engine,(raw water cooled), then the raw lake/ocean water will also circulate through your heater.

[Car2n]

The engine is raw water cooled.

[canoel]

So then yes the same water that circulates through the engine, circulates through the heater. No antifreeze.

[2850Bounty]

"Car2n" post=804062 wrote:
I'm installing a new water heater and wondering about the loop to the engine.

1989 Avanti 2955 with a single 460 Cobra.

I'm installing a 6 gallon heater (this coming weekend) much like the original unit and I'd like to know if the heat loop from the engine to the heater is filled with fresh water from the engine cooling system or is it a separate closed loop with antifreeze?

The engine is raw water cooled.

[color]#000088 wrote:
As per Joel, there will not be any Ethylene Glycol coolant being used.

Your new Water Heater will use H2O from the lake/river/ocean to provide engine heat to the WH's heat exchanger (of which is a tube loop within the WH tank).

Supply = port in intake manifold that is up-stream from the thermostat.

Return = suction port in the engine circulating pump, or equivilent suction area.

Other than potential corrosion issues (w/ the WH heat exchanger), and the NOW additional winterizing concerns, your new WH won't know the difference.

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